Re: [RFC PATCH nvme-cli 2/2] nvme-cli/plugins/mi:add support

From: Keith Busch <kbusch@kernel.org>
To: Mohit Kapoor <mohit.kap@samsung.com>
Cc: fam@euphon.net, kwolf@redhat.com, p.kalghatgi@samsung.com,
	qemu-block@nongnu.org, k.jensen@samsung.com,
	d.palani@samsung.com, qemu-devel@nongnu.org,
	linux-nvme@lists.infrared.org, mreitz@redhat.com,
	u.kishore@samsung.com, stefanha@redhat.com, its@irrelevant.dk,
	javier.gonz@samsung.com, prakash.v@samsung.com,
	jg123.choi@samsung.com
Subject: Re: [RFC PATCH nvme-cli 2/2] nvme-cli/plugins/mi:add support
Date: Fri, 9 Jul 2021 09:04:30 -0700	[thread overview]
Message-ID: <20210709160430.GB291156@dhcp-10-100-145-180.wdc.com> (raw)
In-Reply-To: <20210709145352.GA14300@test-zns>

> +int hal_init()
> +{
> +    int retval = -1;
> +    switch (GetSidebandInterface()) {
> +    case qemu_nvme_mi:
> +        retval = qemu_mi_init();
> +        break;
> +    default:
> +        break;
> +    }
> +    return retval;
> +}
> +
> +int hal_open()
> +{
> +    int retval = -1;
> +    switch (GetSidebandInterface()) {
> +    case qemu_nvme_mi:
> +        retval = qemu_mi_open();
> +        break;
> +    default:
> +        break;
> +    }
> +    return retval;
> +}
> +
> +int hal_close()
> +{
> +    int retval = -1;
> +    switch (GetSidebandInterface()) {
> +    case qemu_nvme_mi:
> +        retval = qemu_mi_close();
> +        break;
> +    default:
> +        break;
> +    }
> +    return retval;
> +}
> +
> +int hal_i2c_write(uint8_t *data_out, uint16_t num_bytes)
> +{
> +    int retval = -1;
> +    switch (GetSidebandInterface()) {
> +    case qemu_nvme_mi:
> +        retval = qemu_mi_write(data_out, num_bytes);
> +        break;
> +    default:
> +        break;
> +    }
> +    return retval;
> +}
> +
> +int hal_i2c_read(uint8_t *data_in, uint16_t num_bytes)
> +{
> +    uint32_t retval = -1;
> +    switch (GetSidebandInterface()) {
> +    case qemu_nvme_mi:
> +        retval = qemu_mi_read(data_in, num_bytes);
> +        break;
> +    default:
> +        break;
> +    }
> +    return retval;
> +}

I'm really not a fan of having non-standard interfaces. If you were
going to do that, though, you should create a struct of function
pointers so that you don't need these repetitive "switch (...)"
statements.

But if we're going to have OOB MI support in toolign, they should all
use the same standard defined interface.